gen_include doesn't respect singleton classes

[jeremyevans]

class A; def self.a() [1] end end class B < A; def self.a() [2] + super() end end class C < B; def self.a() [3] + super() end end class D < A; def self.a() [4] + super() end; gen_include C end p D.a => [4, 1]

Should be [4, 3, 2, 1]

[banister]

hehehehe, wow you really went to town :)

Object2module converts classes into modules - and module inclusion does not bring in the singleton class. So this behavior is part of the spec. Note I call it gen_include not 'multi_inherit`.

The behavior is consistent with pure modules:

module A
  def self.a
  end
end

module B
  include A

  a #=> NoMethodError
end

[jeremyevans]

Fair enough. It's just that you described it as real multiple inheritance in the evilr ticket, which should act like classes, not modules.

[banister]

Sorry if i described it that way :( yeah it just makes classes/objects work like modules, i guess i should have made that clearer.

Your other issue (aside from the rb_is_meta_singleton issue) is very interesting, im looking at it now. I have a feeling it could be similar to this behaviour (which is part of the ruby spec:

class A; end
module M; end
class B < A; include M; end
class A; include M; end

B.ancestors #=> [B, M, A, M]

But, actually, i think i'm wrong since in your code the As end up being adjacent. It's confusing because the test for double inclusion is against the method tables, so I would not expect this issue to arise. Nonetheless, i guess i'll step through the code in gdb to figure out what's going on,

cheers